In the fabrication of semiconductor devices such as integrated circuits, memory cells, and the like, a series of manufacturing operations are performed to define features on substrates, such as semiconductor wafers. Some manufacturing operations, such as etching and deposition, include plasma processing operations that are performed in a plasma processing chamber in which a process gas is transformed into a plasma comprising reactive constituents that can perform work on the substrate when exposed thereto. During such plasma processing operations, the substrate is held on an electrostatic chuck in exposure to the plasma. The electrostatic chuck is defined to establish an electrostatic field that attracts the substrate to a supporting surface of the electrostatic chuck, thereby securing the substrate to the electrostatic chuck.
Control of the electrostatic field generated by the electrostatic chuck is important for securing the substrate during the plasma processing operations and for safely removing the substrate from the electrostatic chuck upon completion of the plasma processing operations. Control of the electrostatic field generated by the electrostatic chuck can be complicated by radiofrequency currents that may flow through the electrostatic chuck. It is within this context that the present invention arises.